"Cheating" (in the sense of exploiting/hacking I think you meant it) is easy in offline single-player games, where you can just use a hex editor. Even many multiplayer games are not really well protected against that kind of hacking/cheating.
The way iGP works is totally different. Some have exploited game mechanics and bugs when they've existed, but in those cases we take responsibility and fix it Long story short, it's incredibly unlikely that anyone in the game is cheating in my opinion.
It's not unheard of for the best managers to be beating level 20s at level 16, so the situation is not that abnormal either.
Undoubtedly they are highly competative and are putting much more effort in than others in the league. I'm level 13, was 12 racing against level 16-17 players. I make sure my team are the most highly qualified. I put new engines in each race. Make sure my drivers are trained above level and always 100% health before a race. I make sure my setups are perfect each race, also review all data from previous seasons paying particular attention to other teams strategy. Most importantly though I show up in person for every race (when possible) and manage my tyre temp, boost and DRS in the most effecteive manner I know how. Subsequently won the last two seasons and doing even better this season. If you put the effort in the rewards are there.
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